Make sure you have the patch file (patch.pat), the rom you want to patch with the translation, the drop rom here.bat and the patching utility (xdelta.exe) in the same folder. After doing that, simply drag & drop the rom file in the drop rom here.bat and it will patch your file with the translation, the translated file will have the original filename with a "-patched" in the end.

Q & A:

Q: I get an error when I try to patch my rom
A: Make sure the rom you're trying to patch is not trimmed